Computing and Combinatorics: 7th Annual International Conference, COCOON 2001, Guilin, China, August 20-23, 2001, Proceedings

strongsupportandallprogramcommitteemembers,theirsupportsta?,and subrefereesfortheirexcellentworkwithindemandingtimeconstraints. Iwould alsoliketothankallauthorsforsubmittingtheirpaperstotheconference. I amgratefultoSteveTateforlettingmeusetheACMSIGACTelectronics- missionservice,MinghuiLiforhelpingmecreateconferencewebpages,and RichardCheekforprovidingsystemsupport. Finally,Iwouldliketoexpressmy gratitudetoDing-ZhuDu,XudongHu,andalllocalorganizersfortheirhard workinmakingthismeetingpossibleandenjoyable. August2001 JieWang ProgramCommitteeChairs: YuriGurevich,MicrosoftResearch,USA JieWang,UniversityofMassachusettsLowell,USA ProgramCommitteeMembers: EricAllender,RutgersUniversity,USA BernardChazelle,PrincetonUniversity,USA DannyZ. Chen,UniversityofNotreDame,USA JianerChen,TexasA&MUniversity,USA FrancisChin,UniversityofHongKong,China Kyung-YongChwa,KoreaAdvancedInstituteofScience&Technology,Korea RodDowney,VictoriaUniversityofWellington,NewZealand ErichGr¿adel,AachenUniversityofTechnology,Germany StevenHomer,BostonUniversity,USA ToshihideIbaraki,KyotoUniversity,Japan TaoJiang,UniversityofCaliforniaatRiverside,USA Ker-IKo,StateUniversityofNewYorkatStonyBrook,USA D. T. Lee,AcademyofScience,Taiwan XueminLin,UniversityofNewSouthWales,Australia MauriceNivat,UniversityofParis,France R. Ravi,CarnegieMellonUniversity,USA R¿udigerReischuk,UniversityofLub ¿eck,Germany SeinosukeToda,NihonUniversity,Japan LushengWang,CityUniversityofHongKong,China GuoliangXue,UniversityofVermont,USA MihalisYannakakis,BellLabs,USA Referees: DoritAharonov GuojunLi C. K. Poon KlausAmbos-Spies XueLi JohnShepherd DouglasBridges YanjunLi AmitabhSinha MarekChrobak YifanLi S. Skiena XiaotieDeng WeifaLiang MichaelTrick BjarniHalldorsson ShuangLuan KlausWagner PatrickHealy CatherineMcCartin C. A. Wang JohnHine AnilNerode WenpingWang YingpingHuang OjasParekh XiaodongWu XiaohuaJia Chong-DaePark BaogangXu Ming-YangKao Jung-HeumPark YuanshengYang JochenKonemann KunsooPark DongmoZhang TableofConten